Additive technology for forming multi-material samples of “stainless steel – high-entropy alloys” system

The Metal Paste Deposition (MPD) method offers several advantages in producing multi-materials compared to other additive technologies. While there have been studies conducted on multi-material production using this method, they are limited. Hence, a significant objective is to expand the research scope concerning multi-materials produced through the MPD method. This study aimed to examine samples of multi-material systems comprising 316L steel with CoCrFeMnNiW0.25 and 316L steel with CrMoNbWV obtained from metal paste. The investigation involved forming multi-material samples and analyzing the porosity, microstructure, phase composition, and hardness of the 316L steel metal paste after sintering. The findings lead to several conclusions: when forming multi-material samples of the 316L–CoCrFeMnNiW0.25 system, there is no necessity to create a transition zone using mixed 316L steel and CoCrFeMnNiW0.25 powders, as these alloys mix strongly within it. However, in the 316L–CrMoNbWV system, forming a transition zone of mixed powders is necessary to mitigate the effects of uneven shrinkage. Altering the sintering modes for multi-material samples of the 316L–CoCrFeMnNiW0.25 system is recommended; the temperature should be reduced by 30–45 °C compared to the sintering modes for 316L steel. After sintering the metal paste derived from 316L steel, the resulting sample exhibits large and small spherical pores. To minimize these defects, degassing can be employed. Additionally, reducing porosity can be achieved through hot isostatic pressing post-sintering. The microstructure following the sintering of the metal paste from 316L steel consists of coarse austenite grains with minimal ferrite accumulation at the grain interface.